Flexible shaft.



PATENTED JAN. 3, 1905.

R. M. G. PHILLIPS.

FLEXIBLE SHAFT.

APPLICATION FILED MAR. s, 1904.

` Vuseful'Flexible Shaft, of

` UNITED STATEs Patented January 3, 1905.

- PATENT QFFICE.'

YFLEXIBLE si-iAF-r;A

SPECIFICATION forming pm of Letters Patent Np. 77e,s74,vdatee January3,1'905.

`T0 all whom it my'concern.:

Be it known that I', Ross M. G. PHILLIPS, a

Angeles, in the countyof Los Angeles and State of California, haveinvented a new and is a specification. v -V This is a, divisional vcasefrom a former application of mine No. 170,396.

This invention relates to-a flexible shaft which is particularlyadapted. as a device for transmitting power between elements whichrotate with axes notin line; and one .object of the invention is toprovide a ljoint whichis, springy axially, but which will sturdilyresisttorsional strains either way. 4 r

Another object is to provide means whereby lthe joint may be soconnected to shafts that when the joint is flexed itwill at all timesact k upon the shaftstorsionallyand not impart any tensile strains ortendencies to the shafts.A

Other objects and advantages of the present description.

The accompanying drawings illustratethe invention, and referringtheretom'lis asection on'line X2 X2, Fig'. 1. detail view showing the.arrangement of the through the joint. showing inone end aportion-of ashaft attached to the joint. Fig. 2 Fig. 3 is a concentric spirals. f

The invention comprises a plurality of concentric spiral springs'. f

A further feature which, while not vitallto'I the generic invention, butwhich is of considerable value, is the means used for connecting thejoint to a shaft in such al manner as to allow end thrust between thejoint and shaft, so

vas to `permit the change of relative alinement between the shaft andjoint. This gives the device high efiiciency, as it eliminates friconeinside of the other, as shown. is cut spirally for a considerableportion of its ition, lateral strains on the bearings of the length,thus forming, as it were, the intermewhich the following' `filed August22,'1903,Serial I slot 5.

diate portionof each tube into a spiral spring. The cuts-are relativelynarrow, so as to form but terminate'short, as shown, so that the ends ofthe joint comprise solid tubular por-- 11. "pgina pintan ngi lingue 2z,mcs, anni No. 170,396. Dividend this appiimipnmed Muth 8,1904. serai110,197,088.

tions.i These solidjends are vprovided with has a tapered thread 7, uponwhich is screwed vslots 5,'which are constrictcd at their mouths l .byshoulders 6. The outer tube 1 at'each end 60 v an annular nut 8,correspondingly threaded.

' A key 9 is supported at each end of the joint. in the slots 5,extending diametricallyl through the joint, and the keys are'clampedtightly in position by screwing up the nuts 8, which squeeze the splitends ofthe joint together.

place bythe conformation of the slots 5,v the clampingefiect produced bythe nuts 8 prevents any possible displaoementof the keys which isprovided with an elongated slot 11,

l'the shaft l() being slidably fitted within' the f inside tube 4, andthe length of the slot 11 is Figure 1 is a'longitudinal sectional-view.While the keys 9 are mechanically held in 'Y 4and prevents them frombecoming loose and.

suiiiciently greater than the width of the key i 9 so that the shaft andjoint may have a rela# tive longitudinal movement. 8o y.

It should be understood that another shaft order to clearly show theconfiguration of the Alternate tubes are cut with their'spirals runningin the same direction, adjacent tubes The inthus having oppositely-cutspirals.

ner tube 4 .has a left-hand spiral, the tube 3 next to it has aright-hand spiral, the tube 2 has a left-hand l'spiral, and. the tube lhas a right-hand spiral. By this manner of arranging tle spirals thejoint is equally effective in transmitting a `rota-tive force in eitherdirection. It is obvious that a slight sliding movement 4will occurbetween the concentric tubes when the device is in operation, as whenthe joint is flexed the length of the outer are along the length of thejoint will be greater than the length of the inner arc, and as the jointrotates the springs will close up somewhat on the inner arc and spreadout somewhat on the outer are. The curved axial line of the joint willalways have a constant length, inasmuch as the joint is practicallynonstretchable and non-compressible, and owing to the sliding litbetween it and the shafts to which it is coupled the joint will not haveto sustain any stress tending to stretch it or compress it along itslength.y The same holds good in the action on the shafts.

When the joint is under tension transmitting power in a given directionof rotation,

two of the spirals will contract and two will expand. rlfhus whendriving in either direction two of the spiral ribbons will be under atensile strain and two will be under a cornpression strain. rl`heinvention is adapted for use on motor-vehicles, as shown in thebeforenamed application, and when so used the spirals may preferably bearranged so that when rotating to drive the vehicle ahead the outerspiral l will contract, thcl spiral 2 expand, the spiral 3 contract, andthe spiral Ll expand, the contraction of the spirals l and 3counteracting against the expansion of the spirals 2 and 4f. Thus thegreatest eciency is obtained, as the expanding spirals being limited intheir expansion by the contracting spirals transmit power under acompression strain helically, while the contracting spirals beinglimited in their contraction by the expanding spirals transmit powerunder a tensile strain helically sustained.

When the joint revolves in the reverse di rection, it is manifest thatthe spirals l and 3 will expand and spirals 2 and t will contract, andthus only spirals 2 and 3 will counteract against each other; but thisdirection of rotation is maintained so infrequently and for such shortperiods and at such low speeds that the non-counteraction of the outerand inner spirals is of no moment.

What l claim isl. A flexible joint comprisinga plurality of independenttubular members, each member having spiral cuts in its intermediateportion and having uncut ends, the cuts of the adjacent members runningin opposite directions, and removable means for securing said membersone'within the other.

2. A flexible joint comprisinga plurality of concentric tubular membersnested together, each member having a spiral cut, and reinovu one withinthe other.,

able means upon the interior of said members for locking them againstrotation relatively to eacn other.

3. A flexible joint comprising a plurality of concentric tubular membersnested together, each member havingan uncut portion at each end and alongitudinally-extensible, spirallyout intermediate portion, andremovable means for preventing the relative rotation of the respectivemembers.

4. A plurality of longitudinally-extensible spirally-cut tubular membersclosely' tting one Within the other, and keysl in the ends of -thetubes, in combination with shafts which slidably engage the keys.

5. A plurality ot' longitudinally-extensible spirally-cut tubularmembers closely fitting onewithin the other, and keys in the ends of thetubes, in combination with shafts having slots which receive the keys.

6. A flexible joint comprising a plurality of longitudinally-extensiblespirally-cut tubular members closely fitting one within the other, thetubes having slots yin their ends, `keys in the slots and extendingdiametrically through the tubes, yand means for clamping the keys.

7. A tlexible joint comprising a plurality of spirally-cut tubularmembers closely tting one within the other, the tubes having slots intheir ends, keys in the slots and extending diametrically through thetubes, and annular nuts -having tapered internal threads for squeezingthe slotted ends of the tubes to; ward each other and clamping the'leys.

8. A flexible joint comprising a plurality of spirally-cut tubular bersclosely litting i tubes having'slots in their ends., keys in f slots andextending diametrically through I ie tubes, and annular nuts havingtapered internal threads for squeezing the slotted ends of thetubes'toward each other and clamping the keys, in combination with s theen'ds of which have elongated slots which slidably fit the hej lntestimony whereof' have signed my name to this speeiieation, in thepresence of two subscribing witnesses, at Los Angeles, in the county ofLos Angeles and State of California, this 1st dav of "darch, i904.

ll/l. G. PHILLIPS.

Vifitnesses:

GEORGE T. Fl-Montar, A. M. Hour.

IOO

